[Fazorath]

Closes #47

Based on issue-38-cargo-runs (it holds #45 and #48, which aren't on main yet), so the diff is only this ticket. Retarget to main once that branch lands.

What

• cargo.py: get_cargo(client, character_id) reads ship_item_id from the ship endpoint, follows asset paging, keeps only items with location_id = that ship and flag Cargo (ammo counts, blueprint copies out), prices them with the existing market price reader, counts unpriced types, passes ESI's fetched-at through. Malformed ship/asset/price bodies raise ValueError.
• Abyss page: a Fetch from EVE button and status note under each of Cargo before / after. Success fills two decimals and reads "From EVE at HH:MM · N unpriced"; errors show in the critical colour and leave the field alone; signed out says to sign in.
• tk.PhotoImage(master=self, ...) in the app icon: baseline fix, the wallet-page tests failed on Linux without it.

Tests

New test_cargo.py (reader against a fake ESI client) and test_cargo_fetch.py (GUI via gui.App, reader mocked). Full suite: 137 tests under xvfb, all pass except test_theme font load, which fails here only because this Linux box has no Chakra Petch font.

NOT DONE: real-data check

The criterion to confirm against a live character that the hold's flag is Cargo and location_id is the ship's item id is still open. It needs the Windows rig with a signed-in docked character, and the rig can't be reached from this session (no desktop access, SSH off). Don't merge until it is written up here.

[Fazorath]

Live Cargo-flag check not run: the PC is offline and the user won't set up access. Decision (DIS-169): accept the fixture-tested reader; the user confirms on first real use with a docked character. Note this PR is based on issue-38-cargo-runs, since #45/#48 aren't on main.

[Fazorath]

Merging into issue-38-cargo-runs. Linux and Windows CI pass on 3.10 and 3.13. Both macOS jobs never got a runner (no steps ran, 15-minute queue timeout, rerun queued again), so that's GitHub infra, not this code. The live Cargo-flag check is waived per DIS-169: the user confirms on first real use.